Various expedients have been suggested to overcome the difficulties involved in electroplating on aluminum and aluminum alloys, which difficulties are caused by the rapidity with which an oxide film forms on the surfaces of aluminum and aluminum alloy bodies which are exposed to air. The present invention is concerned with an improved method for preparing an aluminum or aluminum alloy body to receive an electrically deposited surface coating by a method which includes the treatment of the body in an alkaline displacement solution, more specifically, in a zincate solution. Zincate solutions, and their use, are known, being disclosed, for example, in U.S. Pat. No. 3,216,835 and in German Pat. No. 731,102.